Iran's policy is a product of the games in Germany during Olympics in the 1930s. The inferior Jessie Owens trounced the superior Germans . Can you imagine the embarrassment to the Iranians if this happened to them.? They are just flat out fearful of looking bad.
Turkish warplanes attack PKK targets after soldier killed in attack (Reuters)
from the article: World Jewish Congress: Ban Iran from Olympics over anti-Israel boycott